Belt-shifting mechanism



July 8 1924. 1,500,238

R. R. cUMMlNs ET AL BELT SHIFTING MECHANISM original Filed June 2o..1919 Patented July 8, 1924.

i UNITED STATES PATENT" OFFICE.

ROBERT R. CUMMINS AND ROBERT W. KREMER, OF CLEVELAND, OHIO, ASSIGNORS T0THE KREMER-CUMMINS MACHINECOMEANY, OF CLEVELAND, OHIO, A CORPORA-BELT-SHIFTING MECHANISM.

Application filed-June 20, 1919, Serial No. 305,606. Renewed November22, 1923.

T0 all whom t may concern:

Be it known that we, ROBERT R. CUMMINS and VROBERT IV. KREMER, citizensof the United States, and residents of Cleveland, county of Cuyahoga,State of Ohio, have jointly invented a new and useful Improvement inBelt-Shifting Mechanism, of which the following is a specification, theprinciple of t-he invention being herein explained vand.

the best mode in which we have contemplated applying that principle, soas to distinguish it from other inventions.

The present improvements, relating, as indicated, to belt VKShifters,are particularly directed to the improvement and simplification ofmechanical belt shifters, in which the belt of a lathe or other machinetool may be shifted along the various steps of the driving anddrivenpulleys, without requiring the operators hand to touch the belt. To theaccomplishment of the foregoing and related ends, said invention, then,consists of the means hereinafter fully described and particularlypointed out in the claims.

The annexed drawing and the following description set forth in detailcertain mechanism embodying the invention, such disclosed meansconstituting, however, but one of various mechanical forms in which theprinciple of the invention may be used.

In said annexed drawing Fig. 1 is a front elevation illustrating theattachment of our improved belt shifter to the driving and drivenpulleys of a lathe,

Fig. 2 is a transverse section through saidshifter; Fig. 3 is a view inperspective of the rack member; Fig. 4: is a transverse f sectionthrough the rack and pinion; Fig.

5 is a plan view of the upper belt-shifting loop and slide; Fig. 6 is aplan'view of thelower loop; Fig. 7y illustrates a detail ofconstruction; Fig. 8 is a section illustratinga modification ofthe-construction; Fig.

9 is a sideelevation of'our apparatus.; and Fig. 10-isa view of` amodification.

In this type ofdevice it is customary to support a rack below andparallel with the driving shafting and the drivingv pulley,

and to then operate a movable element along this rack, with-the movableelement carrying a belt-engaging and shifting loop. It is also commonpractice in the Shifters now in 11S@ t0 Provide e .Similar ,arrangementto be attached to the head stock of the latne or other machine tool onwhich it is used, and to thus give twovmechanicallyY moved elements,each of which engages and shifts the belt-, one `along the ,upper pulleyand one alongthelower.l The disadvantage of this type :of'shifters isthat'they involve considerable mechanical complication, are exaU-shapedsupport 8, which is adjustably mounted'upon a horizontal rod 9,which is in turn supported by pipe fixtures 10 from the ceiling 11.After the vchannel has thus been mounted in the bosses 7 it may beturned to any desired angle to bring its upper and lower surfaces atright angles to the planeof a belt .12, which passes over one of thedriving pulleys'2, 3 and 4 forrthe purposes which will later bedescribed, and

may be locked in this position by means of set screws `13f The loweredge of one of the fianges 14 of the channel member 1`is formed with aseries of grooves or recesses to constitute teeth, and is engaged with aY pinion 15 rotatably mounted in a carriage f 16 which is slidablelongitudinally upon the channel 1 and is operated to thus move byrotation of the pinion 15V by means of aV depending handle or rod 17.

Slidably portion of the carriage 16, and movable transversely thelmovement of said carriage, is a rod 18, carrying `at'its upper end apivoted belt-engaging loop 19. This beltengaging'loop is formed of twoseparate portions removably secured together rand provided withcomplementary semi-oval recesses 20 in their adjacent sides, and ispro-Vvided with extending bosses 21 fitted on either side `of an enlargedend22 on theurod 18. A bolt 23 passes through'the enlarged mounted in aslotiin the lower ics end 22 and the bosses 21andY forms the axis aboutwhich the shifting loop may be'swung,

whileY Iit may be lamresi" a ,any desired positionby means of a. setscrew 24 in the enlarged end 22 and other set screws 25 in the bosses 21in order to properly position the belt-shifting loop about the belt,irrespective of the angle at which the beltY is mounted, which of coursewill vary considerably with different machines.

The operation of the upper belt-shifting loop just described, will bereadily understood from the foregoing description. To shift the belt 12from any one of the steps 2, 3 and 4 to the next adjacent step it isonly necessary to turn the handle 17 to rotate the pinion 15, and thusmove the carriage 16`along the channel member 1. rIhis will of coursemove the belt-shifting loop transversely along the pulleys 2, 3 and'4and will push the belt enclosed within the loop 19 from one step to thenext.

'Extending downwardly from the carriage 16 are/two apertured bosses 30,through which extends a rod 31, upon one end of which is pivotallymounted a bracket 32. The lower portion of this bracket is pro videdVwith `spaced aperturedl lugs 33, between which is pivotally mounted acou pling in which there may be removably inserted a rod 35, having atits lower end a laterally extending beltshifting loop 36. On this secondloop 36 is mounted a handle 37 and the loop will engage over theopposite side of the belt 12 as the belt leaves one of the series ofdrivenfpulleys 38, 39 and 40, which represent the driven pulleys of alathe or other machine tool. n ordinary practice a lathe is mountedalmost vertically below the line shaft from which` it is driven, andthus both sides of the driving belt are vertical, or nearly so. There isordinarily a slight angle given to this belt and this will necessitatethe` lowerloop 36 resting against the belt 12,.but as the inner sides ofthe belt-shift ing loop are perfectly smooth and are beveled or roundedaway from the belt, this continuous friction between the belt and theloop has been found not to injure the belt inany way.

It is possible, however, to avoid the' above action ifA desired. and inFigure 8 we show a single slidable rodv 41 mounted in therespondingly'moved in thesamedirection.

Thus'if 4the Vupper loop 42 is pulled over beneath the outer surfaces ofthe largest tual continuous contact between the loops and the belt. Y

In operation a shift of the belt 12 from a smaller to a larger size ofpulley in the upper pulleys is accomplished by first movin@` the handle37 in a direction to throw O the belt 12 from the lower pulley on whichit is running. The belt is thus slackened and the upper loop may then beactuated by the handle 17 to force the belt. on to the next higher upperloop. In shiftingV in the reverse direction the upper loop is firstactuated by the handle 17 Yto throw oil the belt 12 from the pulley onwhich it is running, and after it has been thrown on to the nextsmallerpulley the handle 37 is used to force the belt on to thenextlarger lower pulley. i

ln some cases where a very wide.driving belt is used the operatinghandle 17 is brought so close to the belt that it cannot be convenientlyoperated with the ordinary mounting. In this clase it isV only necessaryto shortenthe supports 10 at the right end of the raclr 5, as seen in.Figftv This mounting of the rack at a slightangle to the common axis ofthe pulleys 2,; 3 and 4 will throw the handle 17 away from the belt,causing it to stand several inches from the belt at the lower end of thehandle and leaving plenty of room for the loperator to manipulate it. 'l

The advantages of the present mechanism arevits obvious simplicity andease of installation, while a very considerable economy iseifected bymounting .bothup-` per and lower shifting loops from a single support,`which is yof course the channel member 1. This handle4 eliminates anyneed for a lower support, which has been universally used in suchmechanisms, with the attendant extra c ost of manufacture vand ofinstallation. y Y

1t will'be evident that the carriage 16 is ordinarily directly betweenthe two sides of thebelt 12` and as sometimes the pulley size-is sosmall that the/two sides of the belt. arel brought very golose, orit`fis necessary to provide some means for assembling the apparatuswithout letting the belt work against the front of the carriage and ofthe members carried thereon. r semblv is shown in Fig. 10, in which theenlarged end 22 on -the rod 18, 'andy the lugs 21 on the belt :shiftingloop 20A are mounted l side by side instead' of in the Such anv asf`manner in Fig-5, in order to Aoffset thebeltshifting loop 19 withrespect to the inember 18 and the carriage 16. This assembly brings thecarriage outside ,of the space between the two sides of the belt and itis then of course possible to similarly offset the lower belt-shiftingloopto correspond to the vertical plane of the upper loop. Thisassemblyis secured, however, without any change in the construction andby merely using a longer bolt 60 for fastening together theupperbelt-shifting loop and the enlarged end 22 on the rod 18.

Other modes of applying the principle of our invention may be em'ployedinstead of the one explained, change being made as regards the mechanismherein disclosed, provided the means stated by any of the followingclaims or the equivalent of such stated means be employed.

We therefore particularly point-out and distinctly claim as ourinvention 1. In a device of the character described, the combinationwith two aligned reversely mounted step pulleys and a continuousshiftable belt operatively connecting the same, of a guideway mountedadjacent to one of said pulleys and substantially parallel with the axisthereof, a carriage movable along said guideway, a belt shifting loopmounted on said carriage and engaging over the adjacent belt, a secondbelt-engaging and shifting loop also supported from said carriage, andseparate means adapted to actuate said loops to shift said belt on saidtwo pulleys.

2. In a device of the character described, the combination with twoaligned reversely mounted step pulleys and a continuous shiftable beltoperatively connecting the same, said pulleys being mounted at differentvertical levels, of a guideway mounted adjacent to the upper of said twopulleys and substantially parallel with the axis thereof, a carriagemovable along said guideway, a belt-shifting loop mounted on saidcarriage and engaging over the adjacent belt, and a second belt-engagingloop depending vertically from said carriage and engaging over said beltadjacent said vertically lower pulley.

3. In a device of the character described, the combination with twoaligned reversely mounted step pulleys and a continuous shiftable beltoperatively connecting the same, said pulleys being mounted at differentvertical levels, of a guideway mounted adjacent to the upper of said twopulleys and substantially parallel with the axis thereof, a carriagemovable along said guideway, a member slidably mounted on said carriageto move transversely thereof, a depending rod carried on said member andextending to a point adjacent said lower pulley, beltengaging andshifting loops mounted on said member and said rod, and means per.-

mitting independent operation'of said loo-ps to shift said belton saidupper and lower pulleys.

4. Ina device of the character described, the combination with twoaligned reversely mounted step pulleys and a continuous shiftable beltoperatively connecting the same, said pulleys being mounted at differentvertical levels, of a guideway mounted adjacent to the upper o f saidtwo pulley-s and substantially parallel with the axis thereof, acarriage movable along said guideway,'a belt-'engaging and shifting loopslidably mounted transversely in said carriage to allow movement of saidloop to compensate for the different positions of said belt when ondifferent steps of said upper pulley, a depending rod pivotally mountedon said loop tov swing ina plane parallel to the axis of said lowerpulley, and a second loop carried on said rod and engaging over saidbelt adjacent said lower pulley, and separate means adapted to actuatesaid belt-shifting loops independent of each other.

5. In a device of the character described, the combination with twoaligned reversely mounted step pulleys, and `a continuous shiftable beltoperatively connecting the same, said pulleys being mounted at differentvertical levels, of a guideway mounted adjacent to the upper of said twopulleys' and parallel with the axis thereof, a carriage movable alongsaid guideway, a beltengaging and shifting loop slidably mountedtransversely in said carriage to allow movement of said loop tocompensate for the different positions of said belt when on differentsteps of said upper pulley, a depending rod pivotally mounted on saidloop to swing in a plane'parallel to the' axis of said lower pulley, anda second loop carried on said rod and engaging over said belt adjacentsaid lower pulley, and depending means adapted to actuate said carriagealong said guideway to cause said loop to shift said belt on said upperpulley.

6. In a device of the character described, the combination with twoaligned reversely mounted step pulleys and a continuo-us shiftable beltoperatively connecting the 115 same, said pulleys being mounted atdifferent vertical levels, of a guide-way mounted adjacent tothe upperof said two pulleys and parallel with the axis thereof, a

carriage movable along said guideway, a

belt-engaging and shifting loop slidably mounted transversely in saidcarriage to allow movement of said loop to compensate for the differentpositions of said belt when on different steps of said upper pulley, adepending rod pivotally mounted on said loop to swing in a planeparallel to theaxis of said lower pulley, and a second loop carried onsaid rod and engaging over slaidbelt vadjacent said lower pulley, anddepending .139

means adapted to a'otuate said carriage along said guideway to causesaid loop to shift said belt on said upper pulley, and a handle on saidlower loop for moving the same.

7; In a device or" the character described, the combination of aninverted channel member7 said channel having a series of notches formedin one flange there-oa carriage" movable along said channel, and apinion on said carriage engaging in said'v notches in said channel.

8f In a device of the character described,

the combination of a support mounted Substantially parallel With'theaxis of a driving pulley, a carriage movable along said support7 a rodmounted on said carriage to move transversely to the movement of saidcarriage, and a belt-shifting loop mounted on said rod, but in an offsetplane, whereby said loop and rod Will liefin different vertical planes.

`Signed by us, this 16th day of June, 1919.

ROBERT R. CUMMINS. ROBERT W. KREMER.

